Die-casting machine



Aug. 13, 1929..

D. J. CON ANT DIE CASTING MACHINE Filed Aug. 3, 1927 2 Sheets-Sheet INVENTOR Davl' d JConant ATTORNEY Aug. 13, 1929.

.0. J. CONANT DIE CASTING MACHINE Filed Aug. 3, 1927 2 Sheets-Sheet 2 ATTORNEY UNETE DAVID J. CONANT, F MEMPHIS, TENNESSEE, ASSIGNOR TO WESTINGHOUSE ELEC- OFFICE.

TRIO 8cv MANUFACTURING COMPANY, A CORPORATION" OF PENNSYLVANIA.

DIE-CASTING MACHINE.

Application file-d August 3, 1927. Serial No. 210,228.

My invention relates generally to die-casting machines and more particularly to machines for casting rotors for dynamo electric machines.

One object of the invention, generallystated, is the provision of a die casting machine that shall be simple and efficient in operation and capable of being readily and economically manufactured.

A more specific object of the invention is to facilitatethe assembling of molds and rotor punchings in the machine in preparation for the casting operation.-

Another object of the invention is to provide molds that may beyquickly and easily cleaned after each casting operation.

It is also an object of my invention to provide for removing the sprues formed integral with the casting by the act of removing the cast rotor from the molds.

5 Other objects of the invention will, in part, b; obvious and will, in part, appear hereina ter.

This invention is disclosed in the embodiment thereof shown in theaccompanying drawings and comprises the structural features and the combination of elements and arrangement of parts which will be exemplified in the construction hereinafter set forth, andthe scope of the application of which will be indicated in the claims.

For a fuller understanding of the invention, reference may be had to the following detailed description, taken in connection with the accompanying drawings, in which,

Figure 1 is a view,' partly in front elevation and partly in section, of a machine constructed in accordance with my invention.

Fig. 2 is a view, in side elevation, of the machine illustrated in Fig. 1.

Fig. 3 is a vertical, sectional view of the molds utilized in thecasting operation, showing the rotor punchings in position.

Fig. 4 is a bottom plan view of thelo'wer mold of the machine, and

Fig. 5 is a View, in cross section, of a por- I. tion ofthe lower mold shown in Fig. 3, illustrating the manner of connecting the gate chambers toethe molding chambers.

The drawings illustrate a machine comprising, in' general, a body "member'l. that is supported between a pair of side frames 2 and 3, and a pair of molds 4 and 5. As

- shown, the molds 4 and 5 are adapted to hold a pile 6 of rotor punchings.

A frame 7 is movably mounted on the body member 1 and disposed to cooperate with the latter in holding the molds and punch-.

ings in position to receive molten metal under pressure. I

The body member 1 is provided with lugs or lateral extensions 8 to which the supportlng side frames 2 and 3 are secured by means of bolts 9. v

A reservoir 10 is provided for containing the molten metal 11 to be utilized. in the casting operation. a As shown, the reservoir 10 comprises a plunger 14 slidably mounted in a flanged cylinder. The plunger is mounted on a piston 15 which is slidably disposed in the cylinder 12. In this construction, the flanged cylinder is supported in a countersunk seat provided in the upper end of the cylinder 12.

In order that the 'molten metal may be forced out of the reservoir 10 and into the molds and punchings, the plunger 14: is operated. The piston 15 which carries the plunger 14 may be actuated in anysuitable manner and, in this construction, it is operated by compressed air which may be admitted, through a conduit opening16, into the lower part of the cylinder, and through a conduit opening 17,'into the upper part of the cylinder. The exhaust from the cylinder 12 may be provided by the utilization of a two-way valve for controlling the compressedoair supply and such practice is so common that. it has not been illustrated.

The top surfaces of the reservoir and the body member are flat, and, in conjunction with the flat surfaces of the lateral extenin manufacture, the lower mold is constructed in two parts which will be referred to as an outer casing 23 and aninnermatrix' 24. The matrix 1s centered in the casing by means of a pin 25 that engages in alined holes 26 and 27 in the casing and the matrix, respectively, and is further secured in position by means of a stud bolt 28, that extends through an opening in the center of the matrix, into the casing. In order that the rotor punchings may be easily centered in proper position in the mold to permit practicing the casting operation, the matrix is provided with an upwardly extending central projection 29 which extends into the shaft openings provided in the punchings and an opening 30 in the upper mold.

The lower mold is provided with casting chambers 31 and gas vents or holes 32 which lead throughthe inner chamber walls. The lowerportionszof the casting chambers 31 are connected to gate chambers in the bottom of the mold. ,iVhen the mold is seated on the mouth of the reservoir, the gate chambers 33 are communication with the reservoir so that molten metal may be forced up through them into the casting chambers.

As illustrated in Figs-.4 and 5, the casting chambers 31 and the gate chambers 33 are oilset relatively to provide a constricted connecting opening 34. lVhen this type of mold construction is followed, the sprues that are formed in the gate chambers when a casting is made, are connected to the casting by comparatively thin strips of metal. Since the cross-sectional area of the metal connecting the sprues 'and main portion of the casting is small, the sprues may be readily broken from the casting without forming a large rough scar. 1

The upper mold comprises an outer body 35and an inner body or matrix 36 that cooperate to form a plurality of mold recesses or chambers 37. The mold chambers are provided with air holes 38 to permit the escape of hot air and gases when molten metal is being forced into the inold. Inasmuch as some of the molten metal often flows into such airholes, it has been found advisable to locate them at the upper ends of the mold chambers between the walls of the inner and the outer parts of the mold, in. order that the I metal which enters the holes may be easily 'cleaned...out by separating the parts otwthe mold. If the parts are only slightly separated, they may be cleaned by shaking the mold or ,by the use of compressed air. I therefore fasten the-matrix 36in the body or casing 35 by means of a screw-bolt 39 that is provided with a shoulder 40 which restricts its entry into a threaded opening provided in the mold matrix 36, thus providing a lostmotion connection between the two parts of the mold. The lost-motion connection keeps the casing 35 and the matrix 36 in operative relation to each other but permits them to be separated sufficiently to be cleaned. The upper portion of the casing '35 is provided with a neck or shoulder 55 to receive a clamping plate and the under surfaces of the matrix and the casing are sha ed to form 'a' seat 35 for receiving the punc ings. 6-.

As shown, the molds 4 and 5 are mounted upon the mouth of the molten-metal reservoir. The means for clamping the molds in position: during acasting operation, comprises the movable vertical frame 7 the side members 41 and 42 which are movably mounted in bearings 43 disposed .in the lugs 8 that are provided to connect the body member and the supporting frames. Each side memberv is Provided with collars 44 to limit their degree of travel. The lower ends of the side members 41 and 42 of the clamping frame 7 are connected by a. base or cross beam 45, and their upper ends are connected by a somewhat similar cross beam 46. The top beam orcross memberis fastened to the top portions of the side members by means of bolts 47;, and each side member is provided with a series of holes 48 so that the beam niay be adjusted at any desired height.

In order to provide for moving the clamping frame 7 either upwardly or downwardly when desired, its base or cross beam is connected, by means of a rod 49, to the piston 20 disposed in the cylinder 19 in'the lower part of the body member. For the purpose of moving the piston 20 upwardly and downwardly, the cylinder is connected to a source of hydraulic pressure (not shown) by means of pipes 50 or openings in its upper and lower portions.

A pressure plate 51 is secured to the central portion of the top beam 46 of the clamping frame by means of a clevis and bolt 52 in a position to bear against the upper mold when the frame is moved downwardly.

In describing the operation of the machine, it will be assumed that the clamping frame 7 is in its uppermost position and that the plunger 14 in the molten-metal reservoir is in its lowermost position. A charge of molten'metal for use in the casting. operation is introduced into the reservoir. The lower mold 5 is then seated on the reservoir,.with its gate chambers in communication with the reservoir. The punching-s 6 to be embodied iii-the IOiZOF'CaStIII'g-"QI'G next placed upon the lower mold, and the upper mold 4 is seated upon the punchings. When the molds and punchings are placed in stacked relation on the reservoir, they are' clamped down over the mouth of the reservoir by means of the clamping frame 7 which is actuated by ad mitting pressure to the upper part of the hydraulic cylinder 19'. When the clamping frame 7 is moved downwardly, its pressure plate 51 engages the top of the upper mold. After the molds and punchings are securely clamped in casting position, compressed air.

is admitted into the lower end of the air cylinder 12 to raise the plunger 14 in th: reservoir and force the molten metal upwardly through the gate chambers 33, into the casting chambers 31 of the lower mold, the channels provided in the punchings for receiving conductors, and the casting chambers 37 in the upper mold.

As soon as the parts have cooled suflicient- 1y, after the casting operation, the clamping frame is moved upwardly to release the molds and the rotor and to permit them to'be removed. Inasmuch as the molds are not 'bolted or fastened together in any manner,

a few blows of a soft hammer are usually sufficient to knock the upper mold off the rotor.

The rotor is usually held rather tightly in the lower mold by the thin connections to the sprues in the gate chambers. Therefore,

it is usually necessary to clamp the lower.

mold to the casting machine and to pull the castingaway from the mold by means of a hoist or other pulling device (not shown).

do not limit myself strictly to the details shown, since, manifestly, the same may be varied considerably without departing from the spirit and scope of the invention, as defined in the appended claims.

I claim'as my invention: 1. A die-casting machine for casting rotors comprising a frame, a cross member supported by the frame, a plurality of cylinders disposed in the cross member, one of said cylinders constituting-a reservoir for molten metal, a lower mold disposed on the reservoir for molding one end of a rotor, an upper mold for molding the other end of the rotor, a clamping frame slidably mounted in the cross member, a piston disposed in one of the cylinders for actuating the clamping frame to clamp the molds and a rotor body against the mouth of the reservoir, and a piston for forcing metal from the reservoir into the molds and the rotor body clamped between the molds. 2. A die-casting machine for castirgg rotor-s comprising a base, a reservoir disposed in the base, a lower mold disposed over the mouth'of the reservoir, a separate upper mold disposed to hold a rotor body against the lower mold, said upper and lower molds being separated by the rotor body, a frame slidably mounted in the base, a piston for actuating the frame to clamp the molds and a rotor body against the mouth of the reser-' voir.

8. A mold provided with a molding chamber and having a gate chamber communicating with the molding chamber, said gate chamber being offset with relation to and having its axisparallel to. the axis of the molding chamber.

4. A die-casting machine for casting rotors comprising a reservoir, a pair of molds provided with seats for engaging and holding between them a pile of rotor punchings, said molds terminating in the seats, thereby to expose the punchings to facilitate'handling, and means for clamping the molds to the mouth of the reservoir.

5. A die-casting machine for casting rotors comprising a reservoir, an upper mold,

a lower mold provided with a central projection for centering a pile of rotor punchings, each of said molds being provided with seats for engaging and holding'said pile of rotor punchings between them and having exterior walls terminating in the seats, there-,

by to 62513086 the punchings to facilitate han-\ dling, and means for clamping the molds in molding position on the mouth of the reservoir. 1

. 6. Ina die-casting machine, in combination, a body member, a mold adapted to be mounted on the body member, a movable frame carried by the body member disposed to be actuated to clamp the mold in position, means carried by the body member for actuating the clamping frame downward, a 1

metal-discharging means provided in the body member for delivering metal upward, said actuating means for the clamp and the metal-delivering means acting in opposite directions and utilizing the movable frame for absorbing the-strains caused by the operation of the machine.

7. In a die-casting machine, in combination, a machine body, a mold provided with a number of parts adapted to be carriedby the body, a clamping frame for retaining the mold in position, means for actuating the clamping frame and means for delivering metal under pressure to the mold, said clamping-frame-actuating means and metaldischarging means being disposed within the frame to act in opposite directions so that the reactive forces caused bytheir operation is absorbed by the, frame.

8. In a die-casting machine, in combination, a body member, a plurality of cylinders disposed in the body member, a mold adapted to be mounted on the body member, a clamping frame for retaining the mold in position, pistons disposed in the cylinders for operation in opposite directions, one of said pistons beingdisposed' to actuate the clamping frame and the other to deliver metal to the mold, whereby the reactive forces caused by the operation of the pistons are in opposition.

9. In a die-casting machine, in combination, a body member, cylinders formed in opposite ends of the body member, a mold to be mounted on the body member, a movable frame carried by the body member,

' means disposed in one of the cylinders for forcing metal into the mold, and means disposed in another of the cylinders for-actuating the movable frame downward to clamp the. mold to the body member.

10. In a die-casting machine, in combination, a body member, a mold adapted to be gaging and shaping one end only of a rotor,

an upper mold for engaging the other end v only of the rotor, means for holding said molds in engagement with the rotor and means for introducing molten metal. into the molds. 12. A mold for die-casting articles comprising a base, a depression in the base, a

matrix disposed Within the depression having an upwardly extending central projection for engaging a core of an article to be cast, a top portion having a central opening for receiving the upwardly extending projection, said top portion being normally separated from the base by the core of the article to be cast.

13. A die for die-casting rotors for electrical machines, comprising a base portion having a substantially level top provided with mold depressions disposed to receiveone end of a core of a rotor to be cast, and

an upper portion having a substantially lat lower surface provided with mold-depressions disposed to engage the other end of the core, said core consituting separating means for the die portions.

14. In a mold for casting articles, a matrix having a casting chamber, a base portion provided with a gate'opening for communicating with the casting chamber, said gate opening being offset with respect to the casting chamber in such manner that, when an article is cast, the gate will be connected to the casting by across section in which conditions of stress'concentration may be set up whereby the broken from the article.

7 In testimony whereof, I have hereunto subscribed my name this 27th day of July,

DAVID J. CON ANT.

gate may be readily 

